After a very intense and long work week learning the ins and outs of my new job, today I’ve been driving all day visiting plants . In fact by the end of today i’ll have been on the road for eight hours. Why should you care about this? Well as I sit here on the public Wi-fi at a Subway three hours from my house (and two hours and a half from my office), I’ve got what I think are three brilliant pieces planned (and two of them actually have tables made and ready).
Sadly, you’re going to have to wait a while for them (around 700 words is my limit before the sandwich artists start looking at me funny). The first will be a historical perspective on rookies. Afterwards, I’m doing a piece on roles players and “chemistry” (assisted by Nerd Numbers) . Finally, will be a revisit and revision of an old favorite.
Trust me, I think you’ll enjoy them.
Now in the interim I have a few things that I think you’ll enjoy.First a podcast featuring some statheads talking b-ball.
Second is an awesome,awesome piece from Alex at Sports Skeptic.
Yes, I liked it so much I'm breaking out a double Wheaton
Finally a reader HU asked:
Arturo,
Does WOW analysis take into account opp. shooting %? As in, how would WOW analysis conclude on a player who shoots 60% with 15 board per 36m but gives up a 100% shooting percentage and 50 PP36m from his opp. counterpart (and just to prove that he is not helping teammates’ defense, he only hangs out in the attacking half of the court)?
You probably have already covered this and I missed it but just wanted to ask. I noticed opponents shoot a really low AdjFG% versus some players (Rondo, Lebron, Camby, Shaq, etc) and terrific versus others (all of the Wizards – I assume bad coaching, Bargnani, Beasley, etc)
Thanks,
For an answer, I’m breaking out some old school work.
Back in the day, I took a quick pass at calculating Wins Produced adjusted by Individual defense.The main driver was the assertion that David Lee is a bad defensive player and his wins produced are inflated
All numbers are taken from 82 games.com
First off some math explanations:
WP48 = PlayersProductivity(PROD48)– MATE48(Team Blk & Asst Adjustment)-DEFTM48 (Defensive Team Adjust)-RelAdjP48(Average of the first three terms for players playing the same position) +.099
The main term that could be said to drive defensive error is RelAdjP48 (the position adjustment). This term assumes that the player in question is facing average production at his position every night. This is very obviously not the case. Good defensive players can tend to be undervalued in our analysis. By calculating the Prod48 for a players average opponent we should be able to adjust for a players good or bad defensive skills. Given the rush nature of this exercise, I used the Celtics as a baseline to assure total wins produced remained the same. I ended up with an adjusted position adjustment equal to my calculated WP48 for the average opponent +.07. When I have the time to complete the entire league for 2009-2010, I will refine the adjustment
Here’s my adjusted table for a few players of Note. Of the players I looked at here’s the ten best defenders:
- Kevin Durant
- Dirk Nowitzki
- LeBron James
- Dwyane Wade
- Kobe Bryant
- Dwight Howard
- Carmelo Anthony
- Brandon Roy
- Gerald Wallace
- Derrick Rose
Of note, Pau Gasol is a perfectly average defender. Of the Players who might be involved in transactions that I looked at:
Joe Johnson & Amare are both better than average defenders. As for David Lee? He’s the worst in that list above but the story is not quite that simple. 82games claims that he used 72% of the Knicks minutes at C and only 3% at PF. If I work out his opponent’s numbers by position:
PosAdj_P48 Actual OppAdjP48 (PF) Actual OppAdjP48 (C)
David Lee 0.406 0.307 0.519
He is clearly a much better defender as a power forward than as a Center. A sign and trade to a team with a true center (say the Phoenix Suns) would benefit him greatly.
For the handmade version of this (or something very similar) go to Courtside Analyst to see Ty’s wonderful work (where you go for the Stats and stay for the ambiance).
This is something, I will be revisiting (once the game by game dataset & tool that Andres and I are working on is done). After all, we all need projects.
Image courtesy of xkcd.com
Arturo's Silly Little Stats v2.0 
robbieomalley
12/17/2010
I laughed real hard at “all of the Wizards.”
HU
12/17/2010
Thanks for the clarification, Arturo.
Defense is half the game and limiting good shots constitutes most of that, so I liked seeing the defense adjusted wins. It certainly changes perceptions of players – makes some considerably more valuable than they appear from FG%, rebounds, etc, while others considerably less valuable.
Please could you clarify what you mean when you write that RelAdjP48 assumes that a player is facing average production at his position? I was looking at 82games.com for stats on opp. counterparts. They simply display the numbers (FGA, FG%, Reb, Ast, etc) that opp. counterparts put up against players when they are on the court. Is this what you took into account in your analysis? This could even somehow be measured relative to teammates for perhaps more effective results on players.
One of my first impressions when looking at the numbers on 82games was that Rondo is being undervalued. Opponent PGs are ridiculously unproductive against him – he shuts them down – relative to his NBA PG colleagues. I realize that his teammates help him a lot but it is still mightily impressive.
Cheers,
arturogalletti
12/18/2010
HU,
The Position Adjusment simply looks at average production for each position. This means that WP is always worked against average opposition. Team d is calculated (ie the difference between actual opponent production and avg league production) nut it’s calculated at the team level and divided equally by minutes played.
I totally agree on Rondo.
HU
12/18/2010
Arturo,
Would it make more sense to take into account in your defensive analysis, alongside what you already do, what 82games.com does and take the numbers that individual opponent counterparts put up against players? This seems in theory like a more effective way to isolate individual defenders than looking at team defense, which is what you are doing. So what I’m talking about is a combination of the two methods: isolate individual stats, what 82games does, and add team (5 court players) d stats, what you do.
To give two examples that emphasize the effectiveness of looking at individual defense: 1) Kevin Love and 2) Andrew Bogut
So, Kevin Love: opp. PFs, and these numbers are from 82games, average a .465 eFG% against him, which is pretty low. But Love plays alongside Beasley at SF, and when Beasley plays SF, opp SFs average a ridiculously high “I’m don’t play defense” .604. eFG%. Minnesota are terrible at defense, but opposition PFs struggle to score when Love is on the court, and so his individual defensive acumen should be recognized and can only happen, given he is on a bad team, with a formula that takes into account his “individual” success.
Now, Andrew Bogut: opp. Cs average an insanely low 9.8 attempts per 48 mins and a .37o eFG% against him, but Bogut is on the same court as Brandon Jennings, who has below average defensive numbers for a PG. Bogut’s defensive skill should be somehow isolated from his teammates.
Likewise, and reversely, team defense also has to be taken into account in an ideal formula. A PG who gets past Jennings then has to try to get a shot over Bogut, and that is tougher than if Jenning’s teammate was Bargnani, so Jenning’s defensive numbers are helped by his teammates.
The stats seem readily available to examine “individual player” defense more effectively.
Cheers,
Man of Steele
12/18/2010
Wow, thanks a lot Arturo. This is probably the most impressed I’ve been with a basketball blog article since Dr. Berri’s original “explanation of WP” articles. I have a few questions, arising from my ignorance. Does your adjusted equation compare what a player’s opponents actually did in that specific game compared with their opponent’s average performance, or does it instead use the team’s defensive performance adjusted for the strength of the opposing player? Here’s what I mean:
Option 1: Opp.Pl. WP (in game A) – Opp.Pl. WP (total) +(81 more games worth of this)
Option 2: (Team Def. Eff. / Opp.Pl. WP (total)) + (81 more games of this)
Does that make sense?
Also, I think it’s interesting that these numbers actually undermine the WP project to some extent. They favor smaller, quicker, more athletic players far more than does WP (cf. Joe Johnson, Bill Walker, Kevin Durant, etc.) and undervalue bigs who rebound well relative to WP (cf. Kevin Love, Chuck Hayes, Joakim Noah, even Mike Miller, though he’s not a big man).
All in all, great article!
Man of Steele
12/18/2010
Sorry, I didn’t mean to say the same thing HU did. I was typing my post when his went up.